Creating a random ordered list from an ordered list

Question

I have an application that takes the quality results for a manufacturing process and creates graphs both to show Pareto charts of the bad, and also to show production throughput.

To automate the task of testing these statistical procedures I would like to deterministically be able to add records into the database and have the quality tech go to certain graphs and compare to a known good graph. But, I also would like to simulate the results so they would go into the database as if a user was running through the testing process.

One idea I have had is to fill a list with i number good, j number bad1, k number bad 2, etc. And then somehow randomly sort the list before insertion into the database.

So, my question, is there a standard algorithm to take a sorted list of values and create a randomly sorted list?

Answer 1

You'll want to use a shuffle algorithm. Make sure to use a proper shuffle algorithm and not a home-baked one, because it may introduce some form of subtle pattern to the data. See this post by Jeff Atwood about the problem with using "random enough" shuffles.